On the perturbative corrections around D-string instantons
Gava, E, Hammou, A, Morales, J F, Kumar S Narain · CERN Document Server (European Organization for Nuclear Research) · 1999
We study ${\\cal F}^4$-threshold corrections in an eight dimensional S-dual pair of string theories, as a prototype of dual string vacua with sixteen supercharges. We show that the orbifold CFT description of D-string instantons gives rise to a perturbative expansion similar to the one appearing on the fundamental string side. By an explicit calculation, using the Nambu-Goto action in the static gauge, we show that the first subleading term agrees precisely on the two sides. We then give a general argument to show that the agreement extends to all orders.